Should I be concerned?

A while back, I accidentally came upon a new alternative to Grindr while going to redownload grindr to check up on the local gay population. I later found out after making a profile and setting it up, that it's actually primarily for gays in asian, thus meaning that 90% of the guys on there are asians.Considering I already went to the hassle of filling out a profile to see the guys on it, I opted to just check it for a few days and then delete it if nobody relevant messaged me. About 2 days in, a cute guy viewed my profile, and so I viewed his, and this happened a few more times before I opted to just "follow" him. He messaged me a few hours later, and what I thought would be just a generic conversation full of smalltalk and nothingness turned into easily one of the best potentials for a good relationship that I've actually had. We quickly started skyping, and have been doing so regularly ever since. He's currently 12k miles away, but once he's back from visiting his family, he'll be only 4 hours away from me, which isn't bad at all. We've both agreed to meet up once he's back if everything is still going good.The relationship itself is really great, and he's done absolutely nothing wrong that would make me suspicious of him. He's a great guy and we genuinely get along perfectly well.My concern lies with the app that originally led us to meet. I never bothered to open it or delete it, since it was tucked away inside an app folder and forgotten about. I had sort of assumed that he didn't have a use for it anymore, until I went to go delete the app today finally. I went ahead and opened it to erase my information, and I stumbled upon his profile. Nothing has really been updated since we met information wise, but he was showing up as being "online 50 minutes ago", which means he's been still using it, I'm guessing?Should I be concerned that he's still using the app? Is this a normal thing? I don't want to commit to him unless he's willing to commit to me, because I want a good relationship rather than one where I'm constantly trying to battle others.Part of me feels as though it's just insecurity since he's really too good to be true sometimes in how well we get along and how attractive he is, but another part of me is still worried.Should I just ask him nicely if he still uses the app regularly, or should I leave it alone? Not trying to be a jealous boyfriend at all, but I'm still slightly anxious about it.TL;DR: Met a BF through a grindr alternative, it's long distance temporarily, but we have a plan to end the distance as soon as will work for both of us. Everything is great and he's amazing, but I noticed accidentally that he still uses the app we met on? Should I just ask him nicely if he still uses the app regularly (and why), or should I leave it alone? Not trying to be a jealous boyfriend at all, but I'm still slightly anxious about it.